煤基液体燃料生产过程温室气体CO2排放与能效问题研究

基于煤炭化工行业的需要,利用已开发的模型对山西省某地煤种,在不同的气化工艺下（GE—Texaco／Shell）,进行100万t煤基甲醇项目、10万t煤基合成燃料油（间接法）工厂全系统的能源效率、CO2排放量的计算,并对结果进行了初步分析。     

Linker-modified microemulsions for a variety of oils and surfactants

Previously, we reported on the use of hydrophilic and lipophilic linker molecules to enhance the solubilization capacity of chlorinated hydrocarbons using sodium dihexyl sulfosuccinate (SDHS). In this work we extend the use of linker molecules to a wider range of oils and surfactants. The data show that the linker effect works for all the systems studied and that linker-based systems are even more economical than surfactant-only systems for more hydrophobic oils. Using a more hydrophobic surfactant, such as sodium bis(2-ethyl)dihexyl sulfosuccinate (Aerosol-OT), requires a formulation enriched with a hydrophilic linker, whereas the formulation for the more hydrophilic SDHS requires the use of a more lipophilic linker. By considering the properties and appearance of the formulation before contacting with the oil, and by evaluation the coalescence dynamics, we found that hydrophilic linker-rich formulations were preferred. These formulations were tested as fabric pretreatments for removing motor oil and hexadecane from cotton, and as flushing solutions for glass bead columns contaminated with these oils. The cleaning performance of these linker-based systems was superior to common surfactant and pretreatment formulations in the detergency tests, achieving more than 80% removal of motor oil and hexadecane trapped in the packed-column flushing tests.     

Rapeseed residues utilization for energy and 2nd generation biofuels

Lignocellulosic biomass is an interesting and necessary enlargement of the biomass used for the production of renewable biofuels. It is expected that second generation biofuels are more energy efficient than the ones of first generation, as a substrate that is able to completely transformed into energy. The present study is part of a research program aiming at the integrated utilization of rapeseed suitable to Greek conditions for biodiesel production and parallel use of its solid residues for energy and second generation biofuels production. In that context, fast pyrolysis at high temperature and fixed bed air gasification of the rapeseed residues were studied. Thermogravimetric analysis and kinetic study were also carried out. The obtained results indicated that high temperature pyrolysis could produces higher yields of syngas and hydrogen production comparing to air fixed bed gasification.     

Vegetable oils: Effects of processing,storage and use on nutritional values

At the present time, vegetable oils are the source of most of the visible fat in the U.S. diet. They are used as salad and cooking oils, in salad dressing, margarine and shortening. Processing methods include extraction, refining, hydrogenation and interesterification. During storage and use, the products are exposed to oxygen and/or heat, particularly during frying. Processing, storage and use are related to changes in composition, nutritive value and physical characteristics of vegetable oils. Refining removes undesirable minor components present in crude oils. Refined polyunsaturated vegetable oils are the primary dietary source of tocopherols. Hydrogenation modifies physical characteristics and improves sensory and oxidative stability. This process converts some of the polyunsaturated fatty acids to new fatty acid isomers. Although the biochemical effects of these isomers are still being studied, long-term animal feeding trials and human experience have demonstrated that the partially hydrogenated oils in margarines and shortenings are wholesome foodstuffs. Abusive overheating of fat in air sharply decreases its palatability and nutritive value and may create minor amounts of carcinogenic materials. However, long-term animal feeding studies with properly used frying fats have revealed little, if any, effect on life span and incidence of pathological conditions.     

Reduction in greenhouse gases emission in a loop reactor adsorber: Simulations and experiments

Loop reactors may compete with other heat recuperating technologies, like reverse-flow reactors, for catalytic abatement of low-concentration volatile organic compounds (VOC), with the advantage that unconverted flashes are avoided. These were recently demonstrated experimentally by the authors. The main goal of this research is to extend this concept to VOC oxidation and periodic CO₂ adsorption and desorption on a bed packed with catalyst and Zeolite adsorber. Its operation incorporates three steps: combustion-adsorption, desorption and cooling. The optimal timing of these steps, the corresponding flow rates as well as the effect of various operating conditions, are examined experimentally and numerically, in order to achieve an optimal design. In these terms the best CO₂ recovery degree simulated is 60–80% with a corresponding effluent concentration during desorption step that is 15–25 times the stoichiometric values. Yet, in the experimental 3-unit loop-reactor system the CO₂ recovery degree achieved is only 25–30% and the CO₂ concentration during this step is only 3 times the stoichiometric values. Better results require better adsorbents.     

Hybrid plasma-catalytic systems for converting substances of high stability, greenhouse gases and VOC

Three kinds of plasma-catalytic hybrid systems were examined with purpose of improving the techniques for the reduction of greenhouse gases and volatile organic compound (VOC) emissions:

(1)

A new reactor was developed and used for combining the reagent activation in gliding discharges (GD) with the catalytic action of particles moving in the discharge zone. Non-oxidative methane coupling by plasma action in the presence of a moving bed of Pt and Pd catalysts was examined. Acetylene and soot were the main products formed in the homogeneous plasma system (without a catalyst) and with alumina-ceramic particles. In the presence of Pt and Pd supported on alumina ceramic particles, two effects were noticed: ethylene and ethane became the main products instead of acetylene, and the soot formation was strongly reduced.

(2)

Plasma-catalytic methane conversion with CO₂ was studied in a dielectric-barrier discharge (DBD) reactor which was packed with selected materials: alumina ceramic carrier, Ag, Fe, and Pd catalysts, and Na-ZSM-5 zeolite. It was found that the tested catalysts were active under the process conditions. The catalytic action of palladium was the most pronounced.

(3)

The conversion of trichloromethane in mixtures with air was investigated with the use of a hybrid system composed of GD and a stable bed of catalysts containing Cr₂O₃, MnO₂ and platinum. Chlorine was the main reaction product with a minor share of hydrogen chloride and tetrachloromethane. Due to the catalysts used in this experiment, the overall CHCl₃ conversion was increased, whereas the unwanted CCl₄ formation was nearly constant.

On the basis of these experiments, one can conclude that hybrid systems which combine plasma activation of reagents with the action of solid catalysts may be useful for processing gaseous substances, including those of high stability. It was confirmed that the catalyst localization inside or near the plasma zone is the indispensable condition for high efficiency of the hybrid systems.     

Interfacial energy for solutions of nanoparticles,surfactants, and electrolytes

The addition of surfactants to modify the surface property of nanoparticles (NPs) from hydrophilic to hydrophobic also enhances their interfacial properties. Several approaches were previously proposed to calculate the surface tension/interfacial tension (IFT) for different systems in the presence of NPs, surfactants, and electrolytes. However, most of these approaches are indirect and require several measured parameters. Therefore, a mathematical model is developed here to calculate the surface tension/IFT for these systems. The developed model takes into account the cohesive energy due to the interaction of the surfactant CH₂ groups, the electric double layer effect due to the interaction among the ions of NPs, surfactants, and electrolytes, and the dipole–dipole interaction of NPs and electrolytes. The developed model is compared and validated with the laboratory experimental data in literature. The results reveal further understanding of the mechanisms involved in stabilization of oil/water emulsion in the presence of NPs, surfactants, and electrolytes.     

Factors affecting oil/water interfacial tension in detergent systems: Nonionic surfactants and nonpolar oils

Because earlier model detergency studies have shown that oil/water interfacial tension is critically important in oil removal processes, factors affecting the interfacial tension between detergent-range nonionic surfactant solutions and paraffin oil have been examined. For a given hydrophobe, equilibrium interfacial tension values increase with the length of the ethylene oxide chain in the hydrophile, because of the attendant decrease in overall surface activity. For a given degree of ethoxylation, commercial nonlphenol ethoxylates reduce interfacial tension more effectively than their secondary alcohol-based counterparts, and these in turn are more effective than commercial primary alcohol ethoxylates. Furthermore, monodisperse primary alcohol ethoxylates reduce interfacial tension more effectively than broad-range ethoxylates with similar cloud points. This observed order of effectiveness is attributed in part to variations in the extent of fractionation that occur as nonionic surfactants divide between the oil and water phases. Equilibrium interfacial tension values produced by commercial nonionic surfactants are significantly more dependent on concentration and temperature than those obtained with monodisperse ethoxylates. However, the time-course for lowering interfacial tension exhibited by monodisperse ethoxylates varies with concentration and temperature to a greater extent than that displayed by commercial products. These findings are accounted for by the combined effects of the changes in relative surface activity and partitioning that occur as the concentration and temperature are varied. An imidazoline-based quaternary fabric softener markedly increases the interfacial tension immediately following phase contact, whereas equilibrium values are only slightly higher in the presence of the softener. Appatently, preferential adsorption of the softener occurs at the interface, followed by adsorption of the nonionic surfactant at the new softener/water interface. Builders and electrolytes have no significant effect on the interfacial tension between aqueous nonionic surfactant solutions and paraffin oil. Terg-O-Tometer results demonstrate the correlation between oil/water interfacial tension and detergency.     

Vegetable oils and animal fats as alternative fuels for diesel engines with dual fuel operation

Vegetable oils and animal fats are applicable as fuels in standard diesel engines after having adapted the fuel system for electronically controlled dual fuel regime oil/fat-fossil diesel. In this contribution, performance and emission characteristics of the engines running on rapeseed oil, lard, or chicken fat are given and compared to those of fossil diesel and fatty acid methyl esters. The results of engine tests of these fuels show a decrease in maximum power and maximum torque in comparison to fossil diesel due to a lower energy content of triacylglycerols. These values are influenced also by a type of the engine used at testing. When compared to fossil diesel, the opacity of oil/fat based fuels is higher for an engine with lower injection pressures while it is lower for an engine with higher injection pressures. The level of both controlled and uncontrolled emissions is low for all tested biofuels and is low also for the reference fossil diesel. The results of performance and emission tests for rapeseed oil containing 3 and 6 vol.% of anhydrous ethanol are comparable to those obtained for pure oil. In this paper, practical experiences based on long-term operation of adapted vehicle fleet fuelled with oil/fat-fossil diesel are mentioned.     

Separation and energy efficiency of packed apparatuses for purifying gases from aerosols

A mathematical model of the turbulent transport of liquid aerosol particles has been considered using an approach in which the transport of a finely dispersed phase is conditionally described as a diffusion process with mass-transfer theory equations. The main parameter in this formulation is the coefficient of the velocity of particle transport (turbulent migration), which is an analogue of the mass transfer coefficient. The use of flow pattern models with a bulk source of the mass of sedimenting particles in a random packed bed and wire-mesh demisters is demonstrated. The equations for calculating the separation zone length and the process efficiency have been derived with allowance for the inlet section and the back mixing of the gas flow. Some calculation results are given for the aerosol separation efficiency and the energy coefficient compared with experimental data.     

Regeneration of oils used for deep frying: A comparison of active filter aids

A number of products are promoted for the purpose of regenerating used frying oils. These materials are referred to as “active” filter aids. They are purported to adsorb polar compounds, which are the products of oil degradation, and to retain them for removal by filtration. To evaluate some of these materials, portions of a used oil were treated with each of several “active” filter aids and filtered in a commercial-type recirculating oil filter. The triglycerides and any adsorbed compounds were extracted from the filter cake with a series of increasingly polar organic solvents. The composition of each of the filter cakes was quantitatively determined. The materials tested in this study were diatomaceous earth, acid-activated bleaching earth, activated aluminas, silica, carbon and synthetic magnesium silicate. Significant differences in the adsorbent characteristics of the materials were found. Adsorption of polar oil degradation compounds ranged from 2 mg of polar compounds per gram of diatomaceous earth to about 200 mg/g magnesium silicate.     

Main methods for decreasing the emission of greenhouse gases formed in the production and processing of fossil fuels

The quantitative characteristics of methods proposed for decreasing the greenhouse effect of CO₂, CH₄, and NO _x formed in the production and combustion of solid, liquid, and gas fuels are compared: change from the combustion of one type of fuel to another; the pumping of CO₂ into aquatic environments, underground voids and lakes, and coal and gas-bearing (oil-bearing) beds; the chemisorption of CO₂ by rocks; the combustion and utilization of coalmine and associated methane; and photosynthesis. Parameters were proposed for evaluating the relative efficiency of well-known methods for decreasing the anthropogenic green-house effect of these gases.     

Food wastes and sewage sludge as feedstock for an urban biorefinery producing biofuels and added-value bioproducts

The updated Bioeconomy Strategy document “A sustainable bioeconomy for Europe: strengthening the connection between economy, society and the environment”, which was issued by the European Commission in October 2018, encourages the exploitation of organic wastes according to a pyramidal hierarchy in which the extraction of valuable biomolecules, which will be used as they are or as precursors of high-added-value compounds, is a priority in biofuel production. This review considers a biorefinery platform in which food waste and sewage sludge are adopted to produce volatile fatty acids (VFAs) through a dark fermentation process. VFA fermentation is optimized by slightly acid pH (6–7), short hydraulic retention time (1–7 days) and high organic load rate (more than 10 gTS L⁻¹ d⁻¹). Attention has been focused on VFA exploitation for polyhydroxyalkanoate (PHA) production via a ‘feast and famine’ strategy performed in sequencing batch reactors. The obtained PHA yields are around 0.4–0.5 gPHA gCOD⁻¹. Moreover, VFAs allow for the production of biofuels, such as hydrogen and methane, through single- or double-staged anaerobic digestion. Innovative bioelectrochemical upgrade strategies for biogas helps producers to obtain biomethane for the automotive sector. Moreover, biogas has recently been tested for the production of polyhydroxybutyrate, a biodegradable and biocompatible thermoplastic made by microorganisms from C1 carbon sources (CO₂ and CH₄). Digestates from anaerobic bioreactors are still rich in nitrogen and phosphorus compounds. These latter compounds have been identified as critical raw materials due to their low availability in the European Union and to increasing demand from the growing global population. Thus, nutrient recovery from digestate allows users to close the loop of the ‘circular economy’ approach. © 2019 Society of Chemical Industry     

A comparison of mid-infrared and raman spectroscopies for the authentication of edible oils

Robust, routine, and rapid instrumental methods for the determination of the authenticity of edible oils, and the detection of adulteration, are continually being sought. In this paper, we compare mid-infrared and Raman spectroscopies for their ability to discriminate between oils of differing botanical origin and for their ability to detect added adulterants. Furthermore, we used sufficient numbers of samples to permit a comparison of some of the chemometric methods (linear discriminant analysis, artificial neural networks) available and looked at the results obtained when the two spectroscopic datasets were combined. We show that mid-infrared spectroscopy, in combination with linear discriminant analysis, gave the best classification rates and adulteration detection levels compared to Raman or combined data.     

2D representation of life cycle greenhouse gas emission and life cycle cost of energy conversion for various energy resources

We suggest a 2D-plot representation combined with life cycle greenhouse gas (GHG) emissions and life cycle cost for various energy conversion technologies. In general, life cycle assessment (LCA) not only analyzes at the use phase of a specific technology, but also covers widely related processes of before and after its use. We use life cycle GHG emissions and life cycle cost (LCC) to compare the energy conversion process for eight resources such as coal, natural gas, nuclear power, hydro power, geothermal power, wind power, solar thermal power, and solar photovoltaic (PV) power based on the reported LCA and LCC data. Among the eight sources, solar PV and nuclear power exhibit the highest and the lowest LCCs, respectively. On the other hand, coal and wind power locate the highest and the lowest life cycle GHG emissions. In addition, we used the 2D plot to show the life cycle performance of GHG emissions and LCCs simultaneously and realized a correlation that life cycle GHG emission is largely inversely proportional to the corresponding LCCs. It means that an expensive energy source with high LCC tends to have low life cycle GHG emissions, or is environmental friendly. For future study, we will measure the technological maturity of the energy sources to determine the direction of the specific technology development based on the 2D plot of LCCs versus life cycle GHG emissions.     

低浓度波动二氧化硫气体的处理

低浓度波动SO2气流一般来源于间歇操作的冶炼装置,气体体积流量可能会从100％改变为20％,气体Ф（SO2）也会从20％改变为0。介绍了冶炼烟气制酸装置低浓度波动二氧化硫气体几种技术解决方案及其优缺点,如将波动的气体加入到其它含SO2气流中,采用低温SO2脱除系统或再生式SO2脱除系统,焚烧硫磺以提高原料气SO2浓度。同时介绍了目前电力行业和化工行业处理Ф（SO2）0．1％～3％气体的一些技术解决方案,这些方案可用于硫酸装置尾气处理。     

New isotherm regularity and an equation of state for gases and liquids

In this paper an isotherm regularity has been introduced for gases and liquids based on intermolecular potential energy. The experimental data has been used to demonstrate the validity of the regularity. A non-linearity relationship exists between (Z ? 1)v³ and ρ for all isotherms of liquids and gases. The basis for this regularity is intermolecular potential which is a modified Lennard–Jones potential (9, 6, 3) for repulsive, dispersion, dipole–dipole and longer-ranged interactions. The isotherm regularity is equivalent to a virial-like EOS for which the parameters of the isotherm form the corresponding second, third and fourth virial-like coefficients. The equation of state is simple and ready to use. The parameters of equation of state are determined by fitting isothermal regularity to experimental data. The new equation of state provides excellent results in homogenous gas and homogeneous liquids region to very high pressures while its predictions in gas-liquid transition have more deviations. Densities of 1828 data points of 21 components have been calculated over the entire range of data with a maximum pressure of 1000 MPa. The average absolute deviation between calculated and experimental densities for gases, liquids and gas-liquid transition region are 0.06%, 0.03% and 0.90%, respectively.     

Highly reliable energy-efficient glass coatings for pipes transporting energy carriers, liquids, and gases

Comparative characteristics of known materials which are used to increase the longevity of steel pipes are presented. It is shown that glass enamel coatings provide effective protection from corrosion. The physical and technological characteristics of fused frits (water resistance, impact strength, microhardness) fall within the GOST 24405-80 limits. __________ Translated from Steklo i Keramika, No. 3, pp. 23–25, March, 2007.